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991.
Forward-deployed medical units do not have the capability to warm intravenous (i.v.) fluids before their administration. We intend to demonstrate a field-expedient means of warming i.v. fluids and preventing hypothermia using the flameless heater available in the Meal, Ready to Eat (MRE). Room-temperature and refrigerated lactated Ringer's solution were organized into three data collection groups using either one or two MRE heaters. The temperature change of the fluid was recorded. Average temperature increases ranged from 15.8 to 31.2 degrees C in times ranging from 8 to 20 minutes. Therefore, we conclude that the flameless MRE heater provides a simple, field-expedient means of warming i.v. fluids before their administration.  相似文献   
992.
Cheng YL  Hsu JY  Hsu HH  Yu CP  Lee SC 《Digestive surgery》2000,17(5):528-531
BACKGROUND: Leiomyomas are rare esophagus neoplasms. They are usually solitary, and the diffuse lesion is extremely rare. CASE REPORT: A 19-year-old male presented with a 3-year history of occasional dysphagia and postprandial regurgitation. The chest radiographs showed a huge mass in the posterior mediastinum. Barium esophagograms showed narrowing of the middle third esophagus with proximal dilatation. The fibroesophagoscopy demonstrated multiple submucosal nodules below a level 22 cm from the incisor and covered with intact mucosa. CT scans of the chest showed a long segment of circumferential soft tissue in the posterior mediastinum which encircled and involved the upper two thirds of the esophagus. An intrathoracic esophagectomy with cervical esophagogastrostomy via the substernal route was performed. Grossly, multiple confluent myomatous nodules circumferentially involved the upper and middle third of the esophagus. Histologic findings showed diffuse leiomyomatosis of the esophagus. CONCLUSION: Esophageal leiomyomatosis should be considered in a young patient with long-standing dysphagia in whom smooth, tapered esophageal narrowing on barium study and circumferential esophageal wall thickening on CT scan are seen. An esophagectomy combined with a reconstruction procedure is indicated.  相似文献   
993.
BACKGROUND: Prostasomes are membranous vesicles secreted by prostate gland, and they contain large amounts of cholesterol, sphingomyelin, calcium, and several enzymes. Prostasomes are involved in a number of biological functions. At ejaculation, these prostasomes are expelled with prostate secretions and are to be found in the seminal plasma as seminal prostasomes, which facilitate sperm function in various ways. METHODS: In this review, we discuss the structural and functional role of prostasomes, the various enzyme systems associated with these vesicles, and the biological role prostasomes play in male reproduction. RESULTS AND CONCLUSIONS Prostasomes are pluripotent and well-organized organelles secreted by the prostate gland. Prostasomes are ascribed to have many physiologiocal functions, the primary function being enhancement of sperm capacity. The several enzyme systems, small signaling molecules, and neuroendocrine markers associated with prostasomes reveal the complex nature of these vesicles in regulating sperm viability and vitality. The functional significance of these molecules that regulate complex pathways in these small vesicles is still a matter of dogma. Critical evaluation of the biological processes associated with prostasomes might be helpful in modeling new contraceptive agents, improving the techniques of in vitro fertilization, and in furthering our understanding and treatment of male factor infertility.  相似文献   
994.
995.
Pseudoepitheliomatous hyperplasia in lichen sclerosus of the vulva.   总被引:8,自引:0,他引:8  
Small tentacles or separated nests of squamous cells in the dermis are not uncommonly seen in long-standing vulvar lichen sclerosus (LS) associated with epidermal thickening. We recently encountered a case where separated nests of well-differentiated squamous cells in the dermis were difficult to distinguish from squamous cell carcinoma (SCC). Further biopsies showed similar nests originating from every hair follicle. We postulated a diagnosis of multifocal pseudoepitheliomatous hyperplasia (PEH) to explain this phenomenon. Because we could find no reference to PEH in the setting of LS, we reviewed the biopsies of 92 women with extragenital and vulvar LS with and without carcinoma to determine its frequency and histological appearance. The study population, which excluded the index case, comprised 10 women with extra-anogenital LS, 58 with vulvar LS without carcinoma, and 24 with vulvar LS with carcinoma. The presence of PEH, epidermal thickness, predominant dermal collagen change, degree of inflammation, and presence of fibrin and red blood cells were recorded. The presence or absence of lichen simplex chronicus (LSC), squamous cell hyperplasia (SCH), and differentiated vulvar intraepithelial neoplasia (VIN) were recorded. PEH was identified only in vulvar LS, where it was seen in 7/58 (12.1%) women without carcinoma, 1/24 (8.3%) with carcinoma, and 0/10 (0%) with extra-anogenital LS. Two forms of PEH were seen: predominantly epidermal 7/8 (87.5%) and predominantly follicular 1/8 (12.5%). PEH was associated with increased epidermal thickness, less dermal edema, more dermal inflammation, fresh fibrin, and red blood cell extravasation. In all cases, there was associated LSC, but there was no SCH or differentiated VIN. In conclusion, PEH may explain many of the cases of dermal tentacles and separated squamous nests in vulvar LS with LSC. The association with fresh fibrin and red blood cells suggests that PEH might be a reaction to tissue damage. PEH is distinguished from SCC by its lack of atypia, confinement to the abnormal collagen, and limited growth. The pathologist must be careful about making a diagnosis of PEH in LS with epidermal thickening, looking carefully for basal atypia and other features of differentiated VIN in the overlying epidermis or dermal proliferation. We do not know whether PEH occurs in differentiated VIN and, if it does, how it could be distinguished from SCC.  相似文献   
996.
997.
Alfuzosin hydrochloride for the treatment of benign prostatic hyperplasia.   总被引:1,自引:0,他引:1  
The chemistry, pharmacology, pharmacokinetics, clinical efficacy, and adverse effects of alfuzosin hydrochloride in the treatment of benign prostatic hyperplasia (BPH) are discussed. Alfuzosin is a functionally uroselective alpha 1-adrenergic antagonist indicated for the management of moderate to severe BPH. It can improve urinary voiding symptoms and increase urinary flow rates while causing few cardiovascular adverse effects. When administered as an immediate-release (IR) formulation, alfuzosin must be administered twice or thrice daily. The extended-release (ER) formulations of alfuzosin for once- or twice-daily administration are associated with small variations in peak and trough serum drug levels, which may contribute to the lower frequency of cardiovascular adverse effects reported with ER versus IR alfuzosin. Alfuzosin has been shown to improve patients' perception of quality of life, allowing patients to increase their physical activities and improve their ability to handle day-to-day activities. Less significant improvements in patients' sense of well-being and improved sexual functioning have been reported. The usual dose of alfuzosin for patients with BPH is 2.5 mg twice or thrice daily of the IR formulation or 5 mg of ER alfuzosin twice daily or 10 mg of ER alfuzosin once daily. The Food and Drug Administration is currently reviewing the ER 10-mg formulation for once-daily administration. IR alfuzosin is similar to all other second-generation alpha 1-adrenergic antagonists in mechanism of action, clinical efficacy, and adverse effects. No dosage titration is needed for ER alfuzosin, and its onset of peak action is within days of the start of treatment.  相似文献   
998.
The pharmacokinetics and metabolism of the l-threo isoleucine thiazolidide dipeptidyl peptidase IV inhibitor, di-[2S,3S]-2-amino-3-methyl-pentanoic-1,3-thiazolidine fumarate (ILT-threo) and its allo stereoisomer (ILT-allo) were evaluated in rats, dogs, and monkeys. Both compounds were well absorbed (>80%) in all species, and most of the dose (>60%) was recovered in urine. Metabolites identified in all species included a sulfoxide (M1), a sulfone (M2), and a carbamoyl glucuronide (M3). For both compounds, parent drug had moderate systemic clearance in rats and dogs ( approximately 20-35 ml/min/kg in both species) and lower clearance in monkeys ( approximately 6-9 ml/min/kg). In rats, M1 was present in systemic circulation in concentrations similar to that of parent drug, whereas in dogs and monkeys, exposures to M1 were higher than for parent drug. In dogs, exposures to the sulfoxide metabolite were approximately 2 to 3 times higher after administration of ILT-allo than after administration of ILT-threo. Carbamoyl glucuronidation was an important biotransformation pathway in dogs. Circulating levels of M3 were significant in the dog, and present only in trace levels in rats and monkeys. M3 could be produced in in vitro systems in a NaHCO3 buffer under a CO2-saturated atmosphere and in the presence of UDP-glucuronic acid and alamethicin.  相似文献   
999.
1000.
Projecting future drug expenditures--2003.   总被引:3,自引:0,他引:3  
Drug expenditure projections for 2003 and factors likely to influence drug costs are discussed. The United States continues to face the challenge of increased growth in health expenditures, and drug expenditures are continuing to increase faster than the growth in total health care expenditures. These increases can be largely attributed to an increase in the average age of the U.S. population and technological advancement. On the basis of price inflation and non-price inflationary factors, including increases in volume, shifts in patient and therapeutic intensity, and expected approval of new drugs, a 10-12% increase in drug expenditures in 2003 for the inpatient setting and a 13.5-15.5% increase for ambulatory care settings are forecasted. While few new drugs are expected to greatly influence expenditures in 2003, the continued diffusion of recently approved drugs such as drotrecogin alfa and nesiritide will have a dramatic impact on total drug expenditures and must be carefully considered in the budgeting process. An agent likely to have a significant impact on HIV treatment is enfuvirtide, the first in a new class of antiretrovirals (fusion inhibitors), but its high cost ($10,000-$15,000 per year) may limit patients' access to this medication. An expanded user's guide is provided to assist the reader in appropriate application of this information in the drug budgeting process. Technological, demographic, and market-based changes and changes in public policy will continue to influence pharmaceutical expenditures in the coming year. An understanding of the overall drivers of medication expenditures and vigilance in monitoring pharmaceutical innovation are critical in the effective management of these resources.  相似文献   
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